烘烤过程中烟叶蛋白质与硝态氮代谢规律研究

对烘烤过程中烤烟烟叶蛋白质与硝酸盐代谢规律的研究表明，蛋白质含量随烘烤进程发展逐渐减少，氨基酸含量逐渐增加，且均在变黄中期和定色其有一定个快速变化阶段，烤后烟叶中氨基酸和可溶性蛋白与鲜叶中可溶性蛋白的呈呈高度正相关；蛋白酶活性在烤烤开始后２４ｈ有一个高峰，硝酸的酶活性从烘烤开始就逐渐升高，２４ｈ达到最大值，之后迅速失活，ＮＯ３和ＮＯ２的含量均在烘烤上升，变黄期达到 最大值，在定色阶段快速下降，但烤

Studies on the metabolism of protein and nitrate nitrogen in tobacco leaf during curing

The metabolism of protein and nitrate nitrogen in tobacco leaf during curing was studied by using the electric heated flue curing barn designed and made by Henan Agricultural University in which the temperature and moisture were controlled automatically.The results indicated that the content of protein decreased gradually while the content of amino acid increased with the proceeding of curing.And either of them had a rapid changing stage in the middle of yellowing period and color fixing period.The activity of proteinase reached the peak respectively after curing 24 hours and 60 hours.The activity of nitrate reductase started to increase from the beginning of curing and reached the highest point after curing 24 hours and then lost rapidly.The contents of nitrate and nitrite increased quickly at the initial period of curing and had a maximum at the end of yellowing period;then they decreased rapidly during color fixing stage.But the contents of nitrate and nitrite in flue cured leaf were much higher than those in fresh leaf.The content of nitrate in the fresh leaf is significantly correlated with the activity of reductase,but not the only influcing factor.